Should You Drink Coffee Before or After Breakfast?

Thanks to emphatic endorsements from tech CEOs, Hollywood A-listers and biohacking finance bros, intermittent fasting has become the biggest diet trend of the decade. The eating pattern, which stacks meals into a strict eight-hour daily window, has gained serious traction for its promise of a trimmer waistline, stable blood sugar levels and anti-inflammatory action.

Alongside avoiding snacking late into the night, skipping breakfast and eating a larger lunch is the bedrock of the IF movement, with the eating plan encouraging drinking black coffee in the early hours instead, claiming it can enhance your fast and provide some added benefits.

But recently, wellness-curious TikTok users have been calling this thinking into question, theorising that gulping an Americano on an empty stomach could send your hormones off-kilter. To help us understand the impact of caffeine on the body, and more importantly, if there’s any truth to the claims, we tapped up a registered dietician for all the answers. 

Is it bad to drink coffee on an empty stomach?

When you’ve spent the night tossing and turning into the early hours, a strong coffee from your espresso machine can be just about the only thing that makes getting out of bed bearable. And there’s good news if you fall into the ‘coffee before everything’ camp. “For most people, coffee on an empty stomach isn’t inherently bad – but it can be uncomfortable,” says Sasha Watkins, registered dietitian and head of health at Mindful Chef.

“Coffee stimulates stomach acid and gut movement, which may worsen symptoms like nausea, reflux or anxiety (aka ‘the jitters’), particularly in people who are prone to digestive sensitivity.”

Watkins adds that coffee can even cause a major mid-morning energy crash for some, but it depends how individually sensitive you are to caffeine. “If you tend to feel the effects easily, having your first cup alongside food can soften these effects without taking away the great health benefits,” she adds.

Can drinking coffee before breakfast spike cortisol levels?

From fears around developing ‘cortisol face’ to the trend for swapping stress-inducing HIIT for gentle Pilates, TikTok has been blowing up over cortisol, with influencers claiming high levels can cause everything from tiredness and puffiness to bloating.

But no matter what you eat or drink first-thing, studies have found that cortisol naturally peaks when you wake up regardless – it’s one of the evolutionary biological mechanisms that encourages humans to get up and go, helping us to transition from sleep to wakefulness.

“Cortisol naturally rises in the morning as part of our circadian rhythm, it’s one of the reasons we wake up feeling alert,” says Watkins. “It’s true that caffeine can cause a short-term increase in cortisol, particularly in people who don’t regularly consume it,” she continues.

“For most healthy adults though, this isn’t considered harmful. However, if you already feel anxious, overstimulated or sensitive to caffeine, having coffee immediately on waking may amplify that wired feeling, which doesn’t always feel great.”

If this sounds like a familiar scenario, waiting 60 to 90 minutes before drinking your first coffee can often feel more comfortable in the long-run.

Are the effects of coffee on an empty stomach different for men and women?

“Broadly speaking, the effects of caffeine are similar across sexes, but some women may notice stronger or more variable responses,” notes Watkins. 

“Hormonal fluctuations can influence how quickly caffeine is metabolised, and during certain phases of the menstrual cycle or when using hormonal contraception, caffeine may stay in the system for longer. That can make side effects like jitteriness or disrupted sleep more noticeable.”

That said, she adds that individual tolerance tends to vary far more than sex differences alone, so it’s worth experimenting with the timing of your cuppa and figuring out what feels best for you.

Bottom line, how should we be drinking our coffee?

When it comes to drinking a cup of Joe on an empty stomach, Watkins says that if your body tolerates it well, there’s no need to necessarily re-think your routine. However, if you’re prone to an early morning energy spike followed by a motivation-crushing midday crash, pairing your cuppa with a balanced breakfast could help to make the working day more pleasant.

“As mentioned earlier, a helpful rule of thumb is to wait 60 to 90 minutes after waking, once cortisol levels naturally start to fall in the body, and ideally have your coffee with or right after food,” Watkins reminds.

“Try pairing it with protein and lots of healthy fats, like avocado, olive oil, nuts and seeds,” she suggests, “as this can support steadier energy and gentler blood sugar responses.”